Electrical-resistance alloy.



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.JOH'NT. H. nnmasrnn, .or SCHENECTADY, NEW YORK,.ASSI.GJNDR 'ro GENERAL ELECTRIC COMMNIE, A CORPORATION or NEW YonK.

ELECTRICAL-RESISTANCE ALLOY.

No Drawing. Application To all whom it may concern;

Be it known that I, JOHN T. STER, a citizen of the United States, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and useful Improvements in Electrical-Resistance Alloys, of which the fol lowing is a specification.

his invention relates to alloys for electrical purposes and has for its object the production of a material having a relatively high specific resistance, which may be easily rolled, drawn, or otherwise formed into desired shape.

One of the objects of my invention is to produce a resistance material suitable for use in rheostats and the like.

In my previous sistivity of about seventy times that of copper. This material will withstand va red heat continuously,and under this condition will oxidize very slowly. This material is extremely satisfactory forcertain purposes, such as electric heaters, where a very high resistance is desired and .where it is desired that a high temperature be employed for considerable intervals. This wire is, how ever, renderedrelatively expensive by the fact that it is extremely hard and, therefore,'diflicult to draw and roll. For certain I -purposes, as for instance in rheostat work,

a resistance conductor is desirable which does not havequite such a sistance and which may oxidize more readily K than that described in the patent above referred to. I have found that by greatly increasing-the amount of iron and reducing both the nickel and the chromium, I can produce aresistance material suitable for this purpose. The iron content should be more than while the iron and nickel together should of the alloy. The following composition, given very good results: iron 70 to 75- per cent., nickel 20 per cent, chroper cent, manganese 4 to 2 per H. DEMP- I Patent No. 901,428, I have disclosed a resistance conductor having a rehigh specific reconstitute more than 80%- Specification of Letters Patent.

filed February 1, 1910.

Patented July 5, 1911i). Serial No. 541,335.

manganese constitute from 5 to 10 per cent.

of the content. Wire made from this alloy is found to have approximately twice the resistance of German silver, and may be produced at a cost which is considerably lessthan' that of German silver. The metal may be drawn and rolled as easily as soft iron, and a duced at a very'low cost.

I have described my alloy as being composed of specific materials combined in definite proportions in accordance with the patent statutes, but it is obvious that the materials and proportions may be modified Withoutdeparting from the spirit of my invention, the scope of which is set forth in the annexed claims.

What I claim as new and desire to secure by Letters" Patent of the United States, is-

1. An electrical resistance conductor comprising iron,. nickel, chromium and manganese, the iron constituting more than 50 per cent. of the alloy.

2. An electrical resistance conductor com prising iron, nickel, chromium and manganese, the iron and nickel constituting more than 80 per cent. of the alloy.

' 3. An electrical resistance conductor containing at least 90 per cent. of iron and nickel. v

4. An electrical resistance conductor con taining approximately 75' per cent. of .iron and 20 per cent. of nickel.

- 5. An electrical resistance conductor containing approximately 75 per cent. of iron and 20 per cent. of nickel, the remainder being chromium and manganese.

6. An electrical taming at least 80 ,per cent. of iron and nickel, the remainder being chromium and resistance conductor con-' uniform product may be proand manganese parts chromium to two parts manganese.

8. An electrical resistance 5 taining at nickel, the iron content'being times that of the nickel.

9. An electrical resistance tainmg chromium, manganese,

con least 80 per cent.'of iron and at least three conductor conand 3. combined iron per cent, the iron content being at least three times that of the nickel. a

In witness whereof, I have hereunto set my hand this 31st day of January, 1910.

' JOHN T. H. DEMPSTER. Witnesses: v,

BENJAMIN B. HULL, HELEN ()nronn.

and nickel content of at least 80 10 

